McGregor won the featherweight title at UFC 194 in December 2015, then became the UFC’s first two-weight class champion when he took Eddie Alvarez’s lightweight title at UFC 205 in Madison Square Garden on Nov. 12.

Interim featherweight champion Jose Aldo, who Conor McGregor beat for the title last year, has been installed as the undisputed champion of the 145-pound division, a place he ruled since inception in the UFC until McGregor beat him.

Max Holloway and Anthony Pettis will fight for the interim featherweight title in the main event at UFC 206 in Toronto next month, with the winner expected to fight Aldo in 2017 to unify the titles.

Daniel Cormier was scheduled to defend his light heavyweight title against Anthony Johnson at UFC 206, but he was forced to withdraw from the fight because of an injury.

McGregor is 5-0 in title fights as the challenger, but he has yet to defend a title in either the UFC or in Cage Warriors where he also was a two-weight champion. Since winning the UFC featherweight title with a 13-second knockout of Aldo, McGregor twice fought Nate Diaz at welterweight and then beat Alvarez at lightweight.

In the lead-up to UFC 205, McGregor had said several times that the UFC would have “to bring an army” to take a belt away from him. UFC president Dana White had said several times that McGregor would have to give up one belt to avoid holding up contenders in multiple divisions.

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